British general elections have often evolved from contests between parties into battles between two opposing themes or ideas. In 1964, it was modernity vs the grouse moors; 1979, trade unionism vs individualism; 1983, Cold War strength vs unilateral nuclear disarmament. This year was supposed to be the Brexit election, yet instead developed into something loosely associated with that, but at the same time quite different: it became the intergenerational election.